The hero killer Stain obviously has killed many heros due to his quirk, it makes him make someone be paralyzed temporarily for a while when eating their blood. But depending on their blood type, from blood type O to B or A. O will be paralyzed for the shortest amount of time, and B is the longest. Izuku is blood type O, the random heros blood type is BA, Iidas blood type is B, and idk what Todorokis blood type is so make it random, and the users blood type is their choice if they say